Self-aligning cover spring for a concealed sprinkler

ABSTRACT

A spring may include an annular plate having a central aperture; a plurality of spring members protruding from the annular plate, the plurality of spring members being resiliently flexible and radially disposed around the central aperture; and a plurality of alignment tabs protruding from the annular plate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.12/415,588 filed on Mar. 31, 2009 (now U.S. Pat. No. 8,176,987, issuedMay 15, 2012). The entire disclosures of the above application isincorporated herein by reference.

FIELD

The present disclosure relates to a spring and more particularly to acover spring for a concealed sprinkler.

BACKGROUND

The statements in this section merely provide background informationrelated to the present disclosure and may not constitute prior art.

Fire protection sprinklers are commonly mounted to ceilings ofresidential and commercial buildings. Such sprinklers are often housedwithin an opening in the ceiling in such a manner that the sprinklerdoes not protrude below the surface of the ceiling when not in use. Adecorative cover plate assembly may be installed over the opening in theceiling to conceal the sprinkler, improving the aesthetic qualities ofthe sprinkler system.

In response to heat from a fire, solder holding the cover plate in placemelts and the cover falls away from the sprinkler and the sprinklertrigger mechanism is then activated by the heat of the fire to release aplug device to allow the sprinkler to discharge water below the ceiling.The sprinkler cover assembly may include a spring which may force thecover plate to fall away from the sprinkler once the solder begins tomelt. Such springs are often difficult to install, and difficult toproperly align within the cover plate assembly.

SUMMARY

A spring may include an annular plate having a central aperture; aplurality of spring members protruding from the annular plate, theplurality of spring members being resiliently flexible, the plurality ofspring members being radially disposed around the central aperture; anda plurality of alignment tabs protruding from the annular plate.

A cover assembly for a concealed sprinkler may include a base, a coverplate and a spring plate. The base may include a tubular portion, aflange portion and a plurality of mounting tabs. The flange portion mayextend radially from the tubular portion to form an L-shaped crosssection. The base may be adapted to engage a sprinkler assembly. Thecover plate may be soldered to the mounting tabs of the base. The springplate may be disposed between the cover plate and the flange portion.The spring plate may have a plurality of spring members resilientlycompressed between the cover plate and the flange portion, therebybiasing the cover plate away from the flange portion. The spring platemay include a plurality of alignment tabs protruding therefrom. Thealignment tabs may be adapted to laterally align the spring platerelative to the base.

A fire protection sprinkler system may include a sprinkler, a base, acover plate and a spring plate. The sprinkler may be fluidly connectedto a water pipe. The base may be disposed around at least a portion ofthe sprinkler, and the base may have a tubular portion, a flange portionand a plurality of mounting tabs. The cover plate may engage theplurality of mounting tabs. The spring plate may have a plurality ofalignment tabs and a plurality of spring members. The spring members maybe resiliently compressed between the cover plate and the flangeportion. The alignment tabs may protrude from the spring plate and atleast partially surround the tubular portion. At least partial meltingof solder retaining the cover plate to the flange portion allows thespring members to forcibly disengage the cover plate from the base,thereby allowing the spring plate and the cover plate to fall away fromthe base.

Further areas of applicability will become apparent from the descriptionprovided herein. It should be understood that the description andspecific examples are intended for purposes of illustration only and arenot intended to limit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustration purposes only and arenot intended to limit the scope of the present disclosure in any way.

FIG. 1 is a partial cut-away view of a concealed sprinkler assemblyhaving a cover assembly installed thereon according to the principles ofthe present disclosure;

FIG. 2 is a perspective view of a cover assembly according to theprinciples of the present disclosure;

FIG. 3 is a an exploded perspective view of the cover assembly of FIG.2;

FIG. 4 is a perspective view of a spring plate according to theprinciples of the present disclosure;

FIG. 5 is a side view of the spring plate of FIG. 4;

FIG. 6 is a perspective view of a base aligned to a first set ofalignment tabs according to the principles of the present disclosure;

FIG. 7 is a perspective view of a base aligned to a second set ofalignment tabs according to the principles of the present disclosure;and

FIG. 8 is a cross sectional view of the sprinkler assembly of FIG. 1 ina deployed position according to the principles of the presentdisclosure.

DETAILED DESCRIPTION

The following description is merely exemplary in nature and is notintended to limit the present disclosure, application, or uses. Itshould be understood that throughout the drawings, correspondingreference numerals indicate like or corresponding parts and features.

With reference to FIG. 1, a sprinkler assembly 10 is provided and mayinclude a sprinkler 12, an adapter 14, and a concealed cover assembly15. The sprinkler assembly 10 may be installed above or within anopening 22 in a ceiling 24 of a building, for example. The sprinklerassembly 10 can also be installed in a sidewall of the building, or anyother suitable location. The sprinkler 12 is coupled to a pipe 25 forfluid communication therebetween.

The adapter 14 may have an outer diameter 26, an inner diameter 28, andan end portion 30 fixed to the sprinkler assembly 10. Threads or ribs 32may be formed in the inner diameter 28. The adapter 14 may surround atleast a portion of the sprinkler 12.

The concealed cover assembly 15 may be assembled to the adapter 14 tocover the sprinkler assembly 10 and the opening 22 in the ceiling 24 toimprove aesthetic qualities of the sprinkler assembly 10. The concealedcover assembly 15 may include a base 16, a spring plate 18 and a coverplate 20. When the sprinkler assembly 10 is exposed to a sufficientlyhigh level of heat, the cover plate 20 falls away from the sprinklerassembly 10, as will be subsequently described. At least a portion ofthe sprinkler 12 may then protrude below the ceiling 24, as shown inFIG. 8, and when the sprinkler is triggered, the sprinkler can dischargewater (or any other fire suppressant or extinguishing agent) into thearea of coverage.

Referring now to FIG. 3, the base 16 may include a tubular portion 34, aflange portion 36 and a plurality of mounting tabs 38, which may beintegrally formed from copper, brass, aluminum or any other suitablemetallic or other material. The tubular portion 34 may include an innerdiameter 40, an outer diameter 42 and a plurality of flexible fingers44. The fingers 44 may be disposed at a first end 45 of the tubularportion and may include a plurality of protuberances 46 protrudingoutward from the outer diameter 42. The protuberances 46 may threadablyengage the threads 32 of the adapter 14, such that the tubular portion34 of the base can be received within the inner diameter 28 of theadapter 14 (FIG. 1). It should be appreciated that the adapter 14 andthe base 16 can be configured such that the base 16 engages threadsdisposed on the outer diameter 26 of the adapter 14.

The flange portion 36 may extend radially outward from a second end 48of the tubular portion 34. The flange portion 36 may include a pluralityof notches 50. The mounting tabs 38 may include an axially disposedportion 52 and a radially disposed portion 54, forming a generallyL-shape. The axially disposed portion 52 may extend downward from thesecond end 48 of the tubular portion 34 at the notches 50 (FIG. 3). Theradially disposed portion 54 may extend outward, generally parallel tothe flange portion 36.

With reference to FIGS. 4 and 5, the spring plate 18 may include anannular plate portion 56, a plurality of spring members 58, a first setof alignment tabs 60 and a second set of alignment tabs 62. The annularplate portion 56 may include a central aperture 64 and an outer diameter66 having a plurality of radially disposed notches 68 cut therefrom. Thespring plate 18 may be formed from copper, brass, aluminum, or any othersuitable metallic or other material.

The plurality of spring members 58 are spaced in a circular pattern.Each of the spring members 58 may be integrally formed with the annularplate portion 56 and may include a leg portion 70 and a foot portion 72.The spring members 58 may protrude from the spring plate 18 generallyaway from a first side of the annular plate portion 56. The springmembers 58 may extend therefrom in a direction having a radial componentand an axial direction, such as, for example, at approximately a 45degree angle (or any other suitable angle) relative to the annular plateportion 56 (FIG. 5). The foot portion 72 may extend from a distal end ofthe leg portion 70 in a generally outward radial direction.

The alignment tabs 60, 62 may protrude from a second side of the annularplate portion 56 in a generally axial direction. The first set ofalignment tabs 60 may be longer than the second set of alignment tabs62, i.e., the first set of alignment tabs 60 may extend farther from theannular plate portion 56 than the second set of alignment tabs 62. Thefirst set of alignment tabs 60 are spaced in a circular pattern having afirst diameter. The second set of alignment tabs 62 are spaced in acircular pattern having a second diameter which may be larger than thefirst diameter. The first and second diameters may be substantiallyconcentric with the central aperture 64.

With reference to FIG. 3, the cover plate 20 may be a circular platehaving an inner face 74, and outer face 76, and a lip 78 disposed arounda perimeter of the cover plate 20. The cover plate 20 may have adiameter that is sufficiently large to cover the opening 22 in theceiling 24 to conceal the sprinkler assembly 10 (FIG. 1). The coverplate 20 may be formed from copper, brass, aluminum, or any othersuitable metallic or other material.

The spring plate 18 may be arranged between the flange portion 36 of thebase 16 and the inner face 74 of the cover plate 20 such that themounting tabs 38 of the base 16 may protrude through the notches 68 inthe annular plate portion 56 of the spring plate 18. Depending on thesize of the particular base 16, one of the first or second sets ofalignment tabs 60, 62, respectively, may engage the inner diameter 40 ofthe tubular portion 34 of the base 16. For example, if the base 16 has asmaller inner diameter 40, the first set of alignment tabs 60 may engagethe inner diameter 40 (FIG. 6). In this manner, the first set ofalignment tabs 60 interfere with the inner diameter 40 to preventrelative lateral movement between the spring plate 18 and the base 16,thereby ensuring proper alignment therebetween. In this configuration,the flange portion 36 of the base 16 may rest on the second set ofalignment tabs 62, while the longer first set of alignment tabs 60 atleast partially protrude up within the tubular portion 34 of the base16, engaging the inner diameter 40 (FIG. 6).

Alternatively, if the base 16 has a larger inner diameter 40, the secondset of alignment tabs 62 may engage the inner diameter 40, while theflange portion 36 abuts the annular plate portion 56 of the spring plate18 (FIG. 7). In this configuration, interference between the second setof alignment tabs 62 and the inner diameter 40 prevents relative lateralmovement between the spring plate 18 and the base 16, thereby ensuringproper alignment therebetween.

It should be appreciated that in either of the above configurationsshown in FIGS. 6 and 7, the first or second alignment tabs 60, 62 maynot actually contact the inner diameter 40 when the spring plate 18 iscentered on the base 16 (i.e., when the diameters on which the alignmenttabs are disposed are concentric with the inner diameter 40). Rather, asmall gap may exist between alignment tabs 60 or 62 and the surface ofthe inner diameter 40 to prevent the spring plate 18 from binding on thebase 16, while preventing sufficient lateral movement to misalign thespring plate 18 relative to the base 16. In this manner, the alignmenttabs 60 or 62 will maintain alignment between the spring plate 18 andthe base 16 within a predetermined tolerance. It should also beappreciated that the spring plate 18 could include any number of sets ofalignment tabs (from one set to several sets) to correspond to baseshaving any number of inner diameter sizes.

With the alignment tabs 60 or 62 maintaining proper alignment betweenthe spring plate 18 and the base 16, the cover plate 20 may be mountedto the mounting tabs 38 of the base 16. The inner face 74 of the coverplate 20 compresses each spring member 58, such that the inner face 74contacts the mounting tabs 38 of the base 16 (FIGS. 1 and 2). The innerface 74 of the cover plate 20 may then be soldered to the mounting tabs38 of the base 16, retaining the cover plate 20 against the base 16 withthe spring members 58 resiliently compressed therebetween. In thismanner, the spring members 58 bias the cover plate 20 away from the base16. Proper alignment between the spring plate 18 and the base 16(provided by the alignment tabs 60 or 62) provides a uniform springforce over the inner face 74 of the cover plate 20 to bias the coverplate 20 away from the base 16. Uniform spring force may ensure that thecover plate 20 disengages from all of the plurality of mounting tabs 38substantially simultaneously, thereby facilitating completedisengagement of the cover plate 20 from the sprinkler assembly 10.

Solder 80 is applied to the inner face 74 of the cover plate 18 and themounting tabs 38 (FIG. 2). The solder 80 may be any suitable type ofsolder to bond the materials of the cover plate 20 and the base 16. Themelting point of the solder 80 may be at a predetermined temperature tofacilitate the release of the cover plate 20 once a predetermined amountof heat conducts through the thickness of the cover plate 20, as will besubsequently described.

As described above, the protuberances 46 may engage threads 32 disposedon the adapter 14, thereby securing the base 16 to the adapter 14. Theconcealed cover assembly 15 may be installed as a modular unit onto thesprinkler assembly 10 once the sprinkler head 12 and adapter 14 areinstalled above the ceiling 24.

Referring now to FIGS. 1-8, operation of the concealed cover assembly 15will be described in detail. As described above, the concealed coverassembly 15 fits onto the sprinkler assembly 10 such that the coverplate 20 covers the opening 22 in the ceiling 24. In response to apredetermined amount of heat from a fire, for example, the solder 80will begin to melt. As the solder 80 melts, the retaining force of thesolder 80 retaining the cover plate 20 against the base 16 begins toweaken. Once the solder 80 is sufficiently melted, the biasing force ofthe spring members 58 will overcome the retaining force of the solder80, forcing the cover plate 20 to fall off of the base 16, away from thesprinkler assembly 10, allowing at least a portion of the sprinkler 12to protrude through the opening 22 and below the ceiling 24 (FIG. 8). Inthe particular embodiment illustrated in FIG. 8, posts 82, having adeflector 84 disposed thereon, are allowed to slide downward withinbrackets 86 in response to the cover plate 20 falling away from thesprinkler assembly 10, thereby positioning the deflector 84 below theceiling 24 in a deployed position.

The composition of the solder 80 should be selected such that the solder80 will melt in response to exposure to a level of heat at which it isdesirable to trigger the discharge of water or other fire suppressing orextinguishing material. Likewise, the spring rate of the spring members58 are selected to allow the spring members 58 to break the bond of thepartially melted solder 80, while preventing the spring members 58 frombreaking the bond of the solidified solder 80.

The sprinkler assembly 10 may also include a bulb-type trigger 88 filledwith a fluid which will expand and break the bulb 88 in response tofurther exposure to heat. Alternatively, a fusible linkage type triggermechanism can also be used, as is known in the art. This ultimatelytriggers the discharge of water or other fire suppressing orextinguishing material out of the sprinkler head 12.

The description of the present disclosure is merely exemplary in natureand, thus, variations that do not depart from the gist of the disclosureare intended to be within the scope of the disclosure. Such variationsare not to be regarded as a departure from the spirit and scope of thedisclosure.

What is claimed is:
 1. A fire protection sprinkler system comprising: asprinkler head; a base disposed around at least a portion of saidsprinkler head, said base having a tubular portion, a flange portion anda plurality of mounting tabs; a cover plate engaging said plurality ofmounting tabs; and a spring plate having a plurality of alignment tabsand a plurality of spring members, said spring members being resilientlycompressed between said cover plate and said flange portion, saidalignment tabs protruding from said spring plate toward said base and atleast partially received within and surrounded by said tubular portionof said base, wherein at least partial melting of solder retaining saidcover plate to said flange portion allows said spring members toforcibly disengage said cover plate from said base, thereby allowingsaid spring plate and said cover plate to fall away from said base. 2.The sprinkler system according to claim 1, wherein interference betweensaid alignment tabs and an inner diameter of said tubular portionprevent misalignment between said spring plate and said base.
 3. Thesprinkler system according to claim 1, wherein a first set of alignmenttabs are radially disposed on a first diameter and a second set ofalignment tabs are radially disposed on a second diameter different thansaid first diameter.
 4. The sprinkler system according to claim 3,wherein said spring plate can be used with multiple different sizedbases, wherein said first set of alignment tabs correspond to a firstbase having a first size and said second set of alignment tabscorrespond to a second base having a second size different than thefirst size.
 5. The sprinkler system according to claim 1, wherein saidspring members protrude at an angle from said spring plate.
 6. Thesprinkler system according to claim 1, wherein said alignment tabsprotrude substantially perpendicularly from said spring plate.
 7. Thesprinkler system according to claim 1, wherein said plurality ofmounting tabs are integrally formed as a unitary member with saidtubular portion and said flange portion of said base.
 8. The sprinklersystem according to claim 1 wherein said spring plate includes anannular plate portion with the plurality of spring members and theplurality of alignment tabs integrally formed with the annular plateportion, said plurality of alignment tabs protruding in a first axialdirection from the annular plate portion and the plurality of springmembers protruding in a second axial direction opposite the first axialdirection from the annular plate portion.